1. Field of the Invention
The invention relates in general to a three-dimensional (3D) video camera and associated control method, and more particularly, to a 3D video camera comprising a plurality of camera lenses of different grades and associated control method.
2. Description of the Related Art
As a result of the popularity of 3D movies, related products, such as 3D televisions, have begun to thrive. However, due to limited 3D video sources, image processing for converting 2D video to 3D video is emerging to increase the amount of 3D video content played by 3D televisions. Meanwhile, the amount of 3D video content is also expanding with the emergence of 3D video cameras and 3D cameras. A 3D camera is taken as an example in the description below, where the 3D camera may be a regular 3D camera or a 3D video camera.
A 3D camera according to the prior art employs two lenses of a same grade to record image data by simulating human eyes. FIG. 1 shows a schematic diagram of an image formation process of a conventional 3D camera. A left camera lens 120 comprises a left lens (L)122 and a left sensing element 124; a right camera lens 130 comprises a right lens (R)132 and a right sensing element 134. The left lens (L)122 forms an image of an object 100 on the left sensing element 124 and outputs a left sensing signal; whereas, the right lens (R)132 forms an image of the object 100 on the right sensing element 134 and outputs a right sensing signal.
A left 2D image processing circuit 126 processes the left sensing signal output by the left sensing element 124 to form a left eye image 128; a right 2D image processing circuit 136 processes the right sensing signal output by the right sensing element 134 to form a right eye image 138. A storage device (not shown) in the 3D camera then stores information of the left eye image 128 and the right eye image 138 to form a 3D video. The left eye image 128 and the right eye image 138 may be a single image or continuous images, and have a same resolution.
It can be seen from the above description that, the conventional 3D camera adopts two sets of camera lenses of an identical grade when generating the left eye image 128 and the right eye image 138, and utilizes individual image processing circuits to generate the left eye image 128 and the right image 138. It is to be noted that the left eye image 128 and the right eye image 138 do not affect each other during formation.
To playback a 3D video with a 3D television, a control circuit in the 3D television in sequence transmits the left eye image 128 to a left eye and the right eye image 138 to a right eye of a viewer; accordingly, the viewer may watch the 3D video.
A lens of a camera generally consists of a plurality of optical elements, and an amount of light that penetrates through the camera lens is controlled by a diaphragm. The sensing element may be a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) sensor. A sophistication of a lens and a resolution of a sensing element as well as an image formation capability are all indices of a grade of the lens, and a lens of a higher grade is naturally higher in cost. Therefore, a conventional 3D camera adopting two lenses of a same grade can be expensive.